A related term...
Polysemy - One word used to describe different things. Also can include phrases, symbolic poetic imagery, and different forms of jargon. Example: Look up the word monster in webster. Then look up the same word in an old law dictionary. Some words have up to 30 meanings. They're meant to hit the senses on a deeper level. They are always done on purpose (this is the main difference between the above related homophones) and are especially used in an historical sense; over time words change their meaning but can still be twisted to serve more than one purpose of meaning.Perhaps this is why it is difficult to teach these in class. It relates to etymology (origins of words) which takes time and study. Worthy study for a greater historical sense in meaning.Often, judging how Polysemes are related makes them ambiguous and vague in nature. I think this works with all languages in one form or another as problems arise when non-native speakers learn a new language. At least it's seen when learning English. Inside information can be conveyed using this device.
I found this post about 'twilight language' to be apt: